A housing structure for a fire detector

Abstract

The utility model discloses a kind of shell structure of fire detector, including body, the inside inside of body is equipped with mixing cavity and air outlet cavity, the air outlet cavity is used to install fan, the installation slot for installing variable light detection module is equipped between the mixing cavity and air outlet cavity, the body surface is equipped with air inlet pipe and air outlet, the air inlet pipe is communicated with mixing cavity, the air outlet is communicated with air outlet cavity, shunt passage is also equipped between the mixing cavity and air outlet cavity, the shunt passage communicates mixing cavity and air outlet cavity.The utility model provides a kind of shell structure of fire detector, improve the inhaled amount of gas, better eliminate local concentration difference, avoid causing damage to variable light detection module simultaneously.

Description

Technical Field

[0001] This utility model relates to the field of fire detector technology, and in particular to a housing structure for a fire detector. Background Technology

[0002] With the rapid pace of urbanization, the number of high-rise, super high-rise, and large-space complexes is increasing rapidly. Traditional point-type smoke and heat detectors can no longer meet the needs for early detection, high sensitivity, and interference resistance. In recent years, "variable light detection modules" based on technologies such as tunable laser absorption spectroscopy (TDLAS), non-dispersive infrared (NDIR), and photoacoustic spectroscopy (PAS) have been gradually introduced into the field of fire detection. These modules can detect characteristic fire gases (such as CO, CO2, CH4, HCN, HCl, etc.) with high selectivity and high sensitivity by changing the wavelength, optical path, or modulation method of light. They can issue alarms tens of seconds to minutes before flames or visible smoke appear, significantly improving the early warning capability of fires.

[0003] The existing technical solutions for intake-type fire detectors mainly involve: a fan inside the detector continuously drawing in ambient air; mixing multiple sources of gas in a mixing chamber; the mixed gas is then pushed to a variable light detection module, where a laser / infrared source and a photoelectric detection unit perform spectral analysis, and finally discharged to the outside through the fan.

[0004] While the above structure discloses the process of collecting and detecting gas, in order to improve the detection accuracy of the detector, it is necessary to increase the intake air volume of multi-source gas, so that more gas can enter the mixing chamber for mixing, thereby eliminating local concentration differences and improving the representativeness of sampling and the detection limit. However, this also brings new problems: the large flow rate requirement will inevitably lead to an increase in fan speed or pump pressure, and the pressure difference between the sampling chamber and the detection chamber can reach 5–20 kPa. This can easily cause microcracks, coating peeling, or resonant frequency drift in the variable light detection module, which usually contains precision optical components (such as MEMS filters, miniature mirrors, hollow optical fibers, or Heriot-Limiter cells). Under long-term pressure and airflow impact, the coating of the mirror surface, the end face of the optical fiber, and the microelectromechanical structure are prone to occur. This can lead to baseline drift, decreased sensitivity, or even complete failure. Utility Model Content

[0005] The purpose of this invention is to provide a housing structure for a fire detector that increases the intake of gas, better eliminates local concentration differences, and avoids damage to the variable light detection module.

[0006] The technical solution adopted in the housing structure of the fire detector disclosed in this utility model is: A fire detector housing structure includes a body, the body having a mixing chamber and an air outlet chamber inside, the air outlet chamber for mounting a fan, an mounting groove for mounting a variable light detection module between the mixing chamber and the air outlet chamber, an air inlet pipe and an air outlet on the surface of the body, the air inlet pipe communicating with the mixing chamber, the air outlet communicating with the air outlet chamber, and a diversion channel communicating between the mixing chamber and the air outlet chamber.

[0007] As a preferred embodiment, a through hole is provided above the air outlet cavity, the air outlet is set at a 90-degree angle to the through hole, and a retaining ring is provided around the through hole, the retaining ring being used to limit the assembly of the centrifugal fan.

[0008] As a preferred embodiment, there are several air inlet pipes, and all of the air inlet pipes are connected to the mixing chamber.

[0009] As a preferred embodiment, the mixing chamber is provided with a first pair of interfaces on the side near the mounting groove, and the air outlet chamber is provided with a second pair of interfaces on the side near the mounting groove. The first pair of interfaces is arranged to be upturned, and the second pair of interfaces is located in the mounting groove and is arranged at an angle.

[0010] As a preferred embodiment, the number of mounting slots is N, the number of diversion channels is N+1, and the diversion channels and mounting slots are alternately arranged.

[0011] As a preferred embodiment, a pressure plate is provided corresponding to the mounting groove, and a fixing hole is provided at both ends of the pressure plate. A mounting post is provided inside the body corresponding to the fixing hole, and the pressure plate is fixedly connected to the mounting post by fasteners passing through the fixing hole.

[0012] As a preferred embodiment, the mounting groove is further provided with buckles on both sides, and the pressing plate surface is provided with a slot, and the pressing plate is connected to the buckles through the slot.

[0013] The beneficial effects of the housing structure of the fire detector disclosed in this utility model are as follows: During installation and use, the fan is located in the air outlet cavity, and the variable light detection module is installed in the mounting groove. The variable light detection module connects the mixing cavity and the air outlet cavity. During operation, the fan creates a negative pressure inside the main body, drawing ambient air into the mixing cavity at high speed through the air inlet pipe. Since the mixing cavity is relatively closed, the airflow generates turbulence and reversal within it, allowing the fire characteristic gas to be fully and evenly mixed with the air, eliminating local concentration gradients, thereby improving detection accuracy.

[0014] An independent diversion channel is also provided between the mixing chamber and the air outlet chamber. When the fan continuously draws air, a positive pressure is formed in the mixing chamber. Part of the mixed gas enters the variable light detection module to complete the spectral detection, while the other part is directly discharged into the air outlet chamber through the diversion channel. By adjusting the cross-sectional area of ​​the diversion channel, the airflow entering the variable light detection module can be reduced, avoiding the direct impact of high-speed airflow on the optical components and significantly reducing long-term damage such as coating peeling and microcracks. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the housing structure of a fire detector according to this utility model.

[0016] Figure 2 This is a horizontal sectional view of the housing structure of a fire detector according to this utility model.

[0017] Figure 3 This is a vertical sectional view of the housing structure of a fire detector according to this utility model. Detailed Implementation

[0018] The present invention will be further described and illustrated below with reference to specific embodiments and the accompanying drawings: Please refer to Figure 1 , Figure 2 and Figure 3 A fire detector housing structure includes a body 10, with a mixing chamber 11 and an air outlet chamber 12 inside the body 10. The air outlet chamber 12 is used to install a fan. An installation groove 13 for installing a variable light detection module is provided between the mixing chamber 11 and the air outlet chamber 12. An air inlet pipe 101 and an air outlet 102 are provided on the surface of the body 10. The air inlet pipe 101 is connected to the mixing chamber 11, and the air outlet 102 is connected to the air outlet chamber 12. A diversion channel 14 is also provided between the mixing chamber 11 and the air outlet chamber 12, and the diversion channel 14 connects the mixing chamber 11 and the air outlet chamber 12.

[0019] An outlet hole is provided above the air outlet chamber 12, and the air outlet 102 is set at a 90-degree angle to the outlet hole. A retaining ring 121 is provided around the outlet hole. The retaining ring 121 is used to limit the assembly of the centrifugal fan. Thus, the centrifugal fan creates negative pressure inside the body 10, and draws ambient air into the mixing chamber 11 at high speed through the air inlet pipe 101. Since the mixing chamber 11 is relatively closed, the airflow generates turbulence and reversal motion in it, so that the fire characteristic gas is fully and evenly mixed with the air, eliminating local concentration gradients, thereby improving detection accuracy.

[0020] In the above scheme, there are several air inlet pipes 101, and all air inlet pipes 101 are connected to the mixing chamber 11. By increasing the number of air inlet pipes 101, the air intake volume can be improved. At the same time, different air inlet pipes 101 can be used to draw air from different areas into the mixing chamber 11 for synchronous mixing and detection.

[0021] The mixing chamber 11 is provided with a first pair of interfaces 111 on the side near the mounting groove 13, and the air outlet chamber 12 is provided with a second pair of interfaces 122 on the side near the mounting groove 13. The first pair of interfaces 111 is tilted upwards, and the second pair of interfaces 122 is located in the mounting groove 13 and is inclined. When the variable light detection module is installed, its air inlet end is connected to the first pair of interfaces 111, and its air outlet end is connected to the second pair of interfaces 122. The first pair of interfaces 111 and the second pair of interfaces 122 are not on the same horizontal plane, forming a height difference. The tilting of the first pair of interfaces 111 can prevent the airflow from slowing down and avoid directly impacting the air inlet end of the variable light detection module, so that the gas can flow better inside the variable light detection module.

[0022] The number of mounting slots 13 is N, and the number of diversion channels 14 is N+1. The diversion channels 14 and the mounting slots 13 are alternately arranged so that when the variable light detection module is installed in the mounting slot 13, the airflow is diverted through the diversion channels 14 and the two sides of the variable light detection module, which can better achieve the effect of airflow guidance.

[0023] A pressure plate 20 is provided corresponding to the mounting slot 13. The pressure plate 20 has fixing holes at both ends. The body 10 has mounting posts inside corresponding to the fixing holes. The pressure plate 20 is fixedly connected to the mounting posts through the fixing holes by fasteners. After the variable light detection module is installed into the mounting slot 13, the pressure plate 20 is used to restrict the variable light detection module and fix it in the mounting slot 13. Furthermore, the mounting slot 13 is provided with buckles 15 on both sides. The surface of the pressure plate 20 is provided with a slot. The pressure plate 20 is connected to the buckle 15 through the slot, so that the pressure plate 20 fits more tightly with the variable light detection module and the installation is more stable.

[0024] This utility model provides a housing structure for a fire detector. During installation and use, the fan is located in the air outlet chamber 12, and the variable light detection module is installed in the mounting slot 13. The variable light detection module connects the mixing chamber 11 and the air outlet chamber 12. During operation, the fan creates a negative pressure inside the main body 10, drawing ambient air into the mixing chamber 11 at high speed through the air inlet pipe 101. Since the mixing chamber 11 is relatively enclosed, the airflow generates turbulence and reversal within it, ensuring that the fire characteristic gas is fully and evenly mixed with the air, eliminating local concentration gradients, and thus improving detection accuracy.

[0025] An independent diversion channel 14 is also provided between the mixing chamber 11 and the air outlet chamber 12. When the fan continuously draws air, a positive pressure is formed in the mixing chamber 11. Part of the mixed gas enters the variable light detection module to complete the spectral detection, while the other part is directly discharged into the air outlet chamber 12 through the diversion channel 14. By adjusting the cross-sectional area of ​​the diversion channel 14, the airflow entering the variable light detection module can be reduced, avoiding the direct impact of high-speed airflow on the optical components and significantly reducing long-term damage such as coating peeling and microcracks.

[0026] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit the scope of protection of this utility model. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the essence and scope of the technical solutions of this utility model.

Claims

1. A housing structure for a fire detector, characterized in that, The device includes a main body, which has a mixing chamber and an air outlet chamber inside. The air outlet chamber is used to install a fan. There is an installation slot between the mixing chamber and the air outlet chamber for installing a variable light detection module. The surface of the main body has an air inlet pipe and an air outlet. The air inlet pipe is connected to the mixing chamber, and the air outlet is connected to the air outlet chamber. There is also a diversion channel between the mixing chamber and the air outlet chamber. The diversion channel connects the mixing chamber and the air outlet chamber.

2. The housing structure of a fire detector as described in claim 1, characterized in that, The air outlet cavity is provided with a through hole above it, and the air outlet is set at a 90-degree angle to the through hole. A retaining ring is provided around the through hole, and the retaining ring is used to limit the assembly of the centrifugal fan.

3. The housing structure of a fire detector as described in claim 1, characterized in that, There are several air inlet pipes, and each air inlet pipe is connected to the mixing chamber.

4. The housing structure of a fire detector as described in claim 3, characterized in that, The mixing chamber is provided with a first pair of interfaces on the side near the mounting groove, and the air outlet chamber is provided with a second pair of interfaces on the side near the mounting groove. The first pair of interfaces is inclined upwards, and the second pair of interfaces is located in the mounting groove and is inclined.

5. The housing structure of a fire detector as described in claim 1, characterized in that, The number of mounting slots is N, the number of diversion channels is N+1, and the diversion channels and mounting slots are alternately arranged.

6. The housing structure of a fire detector as described in claim 5, characterized in that, A pressure plate is provided corresponding to the mounting groove. The pressure plate has fixing holes at both ends. A mounting post is provided inside the body corresponding to the fixing holes. The pressure plate is fixedly connected to the mounting post by fasteners passing through the fixing holes.

7. The housing structure of a fire detector as described in claim 6, characterized in that, The mounting groove is also provided with buckles on both sides, and the pressure plate surface is provided with a slot, and the pressure plate is connected to the buckle through the slot.

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